Is remote sensing through 5G antennas possible?

8 points by trompetenaccoun ↗ HN
Many here might already know that the controversial new 802.11bf wifi standard, set to be introduced in 2024, will enable active "remote monitoring" of movements or objects through the microwaves the devices themselves emit. Microwave sensing works similar to the more well known radar or ultrasound.

I'm trying to find out if remote sensing/monitoring is something that's in practice possible with the 5G antennas that are installed everywhere now. I've searched for papers but might not know the exact terminology, so I didn't find anything. I know it's theoretically possible and what made me wonder is that with the new wifi standard they're shortening the wavelength specifically to get higher resolution imagery. I've seen the argument brought up many times that 5G doesn't bring much speed advantages and that many people don't understand why they increased the frequency so much, which creates some problems (like shorter working distance, for example). Now maybe I'm going full conspiracy here, but it would make perfect sense to do this if one of the goals were monitoring the movement of EVERYTHING in the range of the mobile network antennas. Is this a thing that could practically be done? Feel free to tell me I'm crazy, but please do include an explanation with a source for why or why not.

9 comments

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Sounds like tin-foil hat territory to me (especially given that detailed satelite images and normal cellphone tracking would already be available to the actors in this conspiracy),

But, while you're going down the rabbit hole, you could search and research "passive radar":

> Passive radar systems (also referred to as passive coherent location, passive surveillance systems, and passive covert radar) encompass a class of radar systems that detect and track objects by processing reflections from non-cooperative sources of illumination in the environment, such as commercial broadcast ...

You'd need a lot of satellites capable of very high resolution imagery. And even then it wouldn't be exactly the same. There are plans for 5G to go over 50GHz. That would give you a very high resolution! I mean, these EHF frequencies are also what's used in 'millimeter wave scanners' (full body scanners). You could theoretically sense through clothing. It's also nothing like a bird's eye image, you'd have live 3d imagery from the ground, including places that aren't visible from space.

All that ignoring that it's doubtful they'd ever have so many satellites and enough bandwith to transfer all that data. That seems a lot more feasible from the ground with antennas with broadband connections and which are already set up for the transfer of large amounts of data either way.

I doubt it would be used as mass surveillance from satellites. It would probably be used similarly to the old NYPD backscatter vans.
Your not paranoid, it's a thing. Look at company called Polte - they do 'inventory tracking' using 5g. It's far more accurate for geolocation than anything prior.

They can find your cellphone -ane any other 5g device, within meters.

Personally, I think the marketing video here https://www.o-ran.org/ Is one of the creepiest things out there. Yes, it's 'open' - as in the collusion of all relevant companies in the space have agreed on a standard to sell your data faster, and more openly, than ever before. Oran is a specification for building 3rd party apps that sit inside the antennas compute hardware themselves. Not only can your carrier now track the living shit out of you, but so can hundreds of third parties that have 'obtained your permission'.

5g is creepy as fuck, and absolutely promises the cel network will not be usable for a revolution.

Have you tried 'see through walls with wifi' via duckduckgo?

[1] https://spectrum.ieee.org/see-through-walls-by-the-glow-of-y...

[2] https://spectrum.ieee.org/household-radar-can-see-through-wa...

[3] https://hackaday.com/2018/07/02/using-an-ai-and-wifi-to-see-...

[4] https://www.csoonline.com/article/2222896/stealthy-wi-fi-spy...

[5] https://www.media.mit.edu/publications/see-through-walls-wit...

[6] https://dl.acm.org/doi/10.1145/2486001.2486039

and so forth...

Maybe not from the base stations, but from equipment within the rooms. Also probably not on all used frequencies, because the higher they are, the less penetrating of walls, or even glass.

On the other hand, the timing is much more exact. With that much more precise timing

[7] https://en.wikipedia.org/wiki/Stealth_technology#Radar_steal...

&

[8] https://en.wikipedia.org/wiki/Multistatic_radar

&

[9] https://en.wikipedia.org/wiki/Passive_radar

in the general context of

[10] https://en.wikipedia.org/wiki/Cognitive_radio

comes to mind.

Yeah, as far as the first links go I was aware and that's exactly the kind of thing I'm talking about. I'd love to hear from someone who has more knowledge about the engineering of the 5G towers for that reason.

And you're right that there are issues with penetration the higher the frequency. Which is why it's surprising to me they'd use such extremely high frequencies. Something as simple as rain significantly affects the signal with 5G, there's a phenomenon called rain fade. Then there's the problem with indoor penetration. Without having in depth knowledge of the tech it just doesn't make sense to me from a simple physics point of view. The disadvantages seem to vastly outweigh the slightly higher bandwidth, which immediately breaks down anyway as soon as the conditions aren't ideal.

"The disadvantages seem to vastly outweigh the slightly higher bandwidth, which immediately breaks down anyway as soon as the conditions aren't ideal."

That's my thought. Mainly, it seems it would be more expensive because now you need more equipment/towers to maintain, materials and labor aren't cheap.

The work of Dina Katabi shows that it is possible, although she used somewhat customized hardware and antenna:

https://people.csail.mit.edu/dina/

and that was the basis for the new 802.11bf standard. I believe there has been work since then demonstrating sensing use an ordinary router (maybe custom software but no special antenna). This product seems to be based on something similar:

https://gizmodo.com/hex-home-security-is-a-supercharged-moti...

and Amazon seems to have some aspirations in this area:

https://news.ycombinator.com/item?id=27795048

This is all basically radar and you can use microwaves at many frequencies to do all of these things and more (read heart rate, breathing rate, detect motion, get location) so it certainly is also possible with 5G radios. As you mentioned when the frequency gets higher microwaves have difficulty with distance (when it operates at the same frequency as the "water bands" where atmospheric water absorbs it). It also has difficulty with penetration, so if a wall stops them, then the wall will also prevent spying on you with them. So the lower frequencies like normal WiFi are actually better for spying on people because they will go through walls better. Since 5G also includes lower frequencies it should work as well as WiFi for these purposes.

It's somewhat of a mystery to me why the very high frequencies are part of 5G. I've heard that part of it was because those frequencies are currently unregulated since very little operates in that range. So it may just be a spectrum grab. 5G uses lower radio frequencies for voice just like 4G. The higher frequencies may be only for short range high speed data, such as video. So you could screen cast video to your TV with high resolution, but it probably would not reach from the other end of your house through the intervening walls. If they are actually intending to use 40GHz signals for normal phone operation it seems doomed to fail. It seems much more suited to high bandwidth data transfers when right next to a 5G antenna. So maybe you would only get short bursts of 5G throughput as you moved around, but that might be good enough to quickly download a video and be able to watch it at your leisure, but sometimes it would just not work at all, so the best use would be in a room where there is a 5G cell station.

Because of the small size of 5G cells it will be able to track phone locations with much greater accuracy. So location tracking data collected by the cellular companies will be much more precise, perhaps to the degree that it would be possible to tell what any one person is doing approximately from the phone in their pocket, especially if you could monitor heart rate and breathing at the same time. There would be some costs associated with doing this, maybe no modifications to the transmitters and receivers, but some software would need to be running and doing a fair amount of fast computation, which would require bigger and more costly computers in the cell stations. And it would mean more data flowing across the network to some central collection point. That cost might not be enough to be a deterrent though. So it seems like 5G could be intended to spy on everyone and everything. Whether it is currently being deployed that way would be very difficult to find out, it doesn't seem like something anyone involved would want the public to know. It's also possible it could be deployed as an upgrade to the system later on, which may make it easier to deploy with fewer people knowing about it. It's a good question, I'm not sure you'll find anyone able to supply any more of an answer than yes, it's possible...

Good write-up, thanks for that! What you say is largely my take as well. It's just strange they'd use such high frequencies and no one I've talked to about this has been able to explain why. I hoped there might be an mobile network engineer here who might know more. Like you say they could be rolling out regular 5G first, then update it later. If true I don't expect it to stay hidden forever but there's already so much spying through existing networks (including for example US spying on high ranking EU leaders) that most people have gotten almost numb to it and I suspect they'd accept it as yet another way they're tracked and go on with their lives. I don't trust these standard organizations like IEEE and 3GPP. The IEEE P802.11 task group for that Wlan sensing capability is chaired by a guy from Huawei for example. Who in their right mind would think that a good idea, disregarding the questionable nature of that functionality as a regular standard in the first place.